Reflections on chronic pain in gynecologic practice

Europ. J. Obstet. Gynec. reprod. Biol., 18 (1984) 245-254 Elsevier

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Reflections on chronic pain in gynecologic practice M. Renaer Department of Obstetrics and Gynecology, University Hospital Sint - RafaU-Garthuisberg, Catholic University ofL.euven, B 3oo0, L.euven, Belgium

The reflections which follow are inspired by many years spent in diagnosing causes of chronic pain in gynecologic practice, in trying to understand mechanisms of organic, functional or psychogenic pain, and in trying to alleviate it by medical means when possible and by surgical when necessary. The harvest of this endeavor has not been particularly abundant. This has various reasons, one of them being that the problems posed by chronic pain patients are complex. This contribution is devoted to some general reflections. I am grateful to my friends and collaborators for the opportunity offered to me to insert them into this publication. Chronic pain problems are complex experiences

‘Pain is the net effect of incredibly complex interactions of ascending and descending neural systems, biochemical, physiologic and psychologic mechanisms, and neocortical processes that involve dynamic constantly changing activities in most parts of the nervous system, which occur simultaneously. By the time that pain is perceived, it has been submitted to the action of many of the neural systems’ (J.J. Bonica, 1979); and it becomes only manifest or known to others when translated into one of the various forms of pain behavior (Fordyce, 1978). There are good reasons to assume that pain experiences are the integrated result of the three major dimensions of pain: the sensory-discriminative, the motivationalaffective and the cognitive-evaluative (Melzack and Dennis, 1978). We will come back to these dimensions later. In order to correctly evaluate pain complaints and especially chronic pain, we will have to gauge the importance these different aspects assume for the patient. Is pain ever unreal?

There is frequently a discrepancy between a patient’s complaints and the objective findings of the examination; and a patient’s illness behavior not uncommonly seems abnormal. Some patients will describe their pain experience without giving the impression of being in pain, and some seem pleased to say: ‘The treatment you prescribed at the latest visit did not help me any more than the earlier ones, doctor.’ 0028-2243/84/$03.00

0 1984 Elsevier Science Publishers B.V.

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The fact that many patients unconsciously exaggerate their pain may be trying and even irritating for those who endeavor to help, but there is almost never sufficient reason to assume or to say that the pain is imagined or unreal. During the past 35 years this writer has seen very few cases of outright malingering. R. Leriche (1949), after having seen more than his share of difficult chronic pain problems, maintains that those who suffer do suffer as they say, and that by having their attention constantly riveted on their pain, they suffer more than we imagine. ‘The only pain one can endure easily is somebody else’s pain.’ Acute versus chronic pain

It has become increasingly clear during the last two decades that there is a substantial difference between acute and chronic pain situations. Pain is usually called chronic when it has lasted at least six months. Although acute pain episodes entail their own diagnostic and therapeutic problems, these are usually easier to solve than those of chronic pain; diagnosis is mostly easier, treatment more efficient, and there is less opportunity for the development of behavioral patterns characteristic of the chronic pain sufferer. Whereas in acute pain syndromes our attention will primarily be drawn to the diseased organ or system, in chronic pain we will have to concentrate on the personality of the patient, her own reactions and those of the people around her, as much as on her pain complaints, Stembach (1981) rightly draws attention to some effects of chronic pain which may erroneously be interpreted as symptoms of psychological disturbance. He notices that, apart from being affected by sleep disturbance and irritability, which are common symptoms in chronic pain, ‘these patients feel quite exhausted, drained of energy, not merely from lack of sleep but because the continuous pain wears them down...‘, so that these features should not too readily be considered as pointing towards (primary) psychological problems or psychiatric conditions. A comparison of the effects of severe acute pain and severe chronic pain led Sternbach to the conclusion that the effects of acute pain are similar to those of a pronounced anxiety reaction and that those of severe chronic pain are to a large extent similar to the symptoms of a (masked) depression. Several of the symptoms of severe chronic pain are psychological in nature, and are therefore likely to raise the hypothesis that they are psychogenic and, as some like to think, not quite real. It should be pointed out, however, that although the symptomatology of many patients with severe chronic pain to a large extent coincides with that of masked depression, this is surely not the case for all chronic pain patients (J.J. Bonica, 1979). The study of any pain problem should start with a careful analysis of the pain symptoms, but in view of the importance of psychological influences on the pain experience and on pain tolerance, the personality of the patient and her past and present situation should be ascertained. We will therefore dwell, somewhat in extenso, on some of the psychological aspects of chronic pain syndromes. Analysis of the pain complaint

In every field of clinical medicine pain symptoms constitute a valuable aid in establishing a diagnosis. The value of these symptoms depends on the care taken in

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analyzing their characteristics (T. Lewis, 1942; R. Jansse, 1966). We therefore started our own clinical research on chronic pain patients and pain syndromes with the analysis of the pain of some 80 patients in whom chronic pain was certainly, or most probably, due to a definite gynecologic lesion. The localization and nature of the lesions were verified either by laparoscopy or laparotomy (Schockaert and Renaer, 1954; Renaer, 1971, 1973). The characteristics of chronic pain of gynecological origin deduced from these observations are thus based on anatomo-clinical correlations and not on any current theory about mechanisms of visceral pain. In fact, for any such theory to be valid it will have to explain these clinical observations. The clinical characteristics just alluded to are: 1. The most frequent localizations of chronic pain of gynecologic origin. 2. The usual or possible radiations or spread of the pain. 3. The time-intensity relationship during the menstrual cycle. 4. Hyperalgesia of the abdominal wall and of the lower back in chronic gynecologic pain syndromes. 5. Some other useful data. These characteristics will not be described in this paper; it suffices to remark that enough time should be spent on taking a careful history of the pain and its characteristics. The importance of the history and of observing the manner in which it is presented by the patient can hardly be overvalued, and is irreplaceable by any technological exploration. Personality and pain behavior

(a) Pain and psychosomatic interactions We saw earlier that the pain experience in general, and chronic pain in particular, is a complex, integrated experience consisting essentially of the pain sensation, affective and motivational reactions to the pain, a tendency to evaluate whether the pain is threatening to one’s health or life, and communication of the experience to others by the patient’s illness behavior. A detailed overview of the components of the pain experience would make it abundantly clear how psychological factors may influence the diverse aspects of pain provoking disorders and especially chronic pain problems. It would seem that many specialists who are confronted with chronic pain problems are still not sufficiently familiar with the psychology of pain, although it should not be for lack of good texts on this subject (Merskey and Spear, 1967; Sternbach, 1974, 1978; Bond, 1979, 1981; Pilowsky, 1981; Hendler, 1981). On the other hand it does sometimes seem desirable to check the flow of psychodynamic explanations offered by some ‘inspired’ but uncritical psychopathologists. (b) The adoption of the sick role D.A. Drossmann, R.S. Sandler, et al. (1982) found in the U.S.A. that about one quarter of a sample of apparently healthy subjects reported that they had had abdominal pain more than six times in the previous year, and 17% had had

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symptoms that fulfilled a rigorous definition of bowel dysfunction. Commenting on these data Lennard-Jones (1983) asks: ‘Why then do some people seek medical help and others not? Is it that their symptoms are more severe or that they are less able to cope with them? Similarly, why does a patient with longstanding symptoms seek help now? There is no dividing line between health and disease, only between those who shrug of their symptoms, seeking little or no medical help, and those whose lives are affected by them to a greater or lesser extent.’ Any doctor who is confronted with distressed people, with patients repeatedly complaining of pain or with chronic pain patients should be aware of the many, diverse factors that may induce a person to go to a doctor. This observation led D. Mechanic to introduce the useful concept of ‘illness behavior’, defined as ‘the way in which given symptoms may be differentially perceived, evaluated and acted (or not acted) upon by different kinds of persons’ (Mechanic, 1962). It would thus seem that, amongst our chronic pain patients, there is a large self-selected group of persons who has decided to cross the threshold leading to a doctor, and possibly to the sick role, whereas others, in similar circumstances, do not. This may happen under endo- or exogenous influences: social problems, emotional disturbances, conflicts within the family, neurotic personality traits, low complaining threshold determined either by familial or ethnic background. It is clear that the consultant will usually have to spend more time than the family physician to get acquainted with the personality characteristics and with the past and present situation of the patient. This should enable him to interpret the patient’s illness behavior better. (c) Somatic versus psychogenic pain It seems logical, and it is tempting, to distinguish amongst the various causes of chronic pain: (1) organic pain, when it is felt that the pain can be explained by a lesion in an organ or a system; (2) functional, or rather dysfunctional, pain, when it seems to be due to a dysfunction of an organ or a system; (3) psychogenic, when there are reasons to assume that the pain is due primarily to psychological factors; ‘in practice, this usually means that an adequate physical explanation for the pain experience cannot be given, whereas an adequate explanation in psychologic terms can be given’ (Sternbach, 1974). The reality of chronic pain experiences is, however, much more intricate. Some physiological effects of chronic pain

It might be supposed that personality profiles of patients with chronic psychogenic pain are different from those of persons with organic pain (Renaer, 1971). It has, however, been shown by several authors that in many cases this distinction does not hold (Woodforde and Merskey, 1972; Sternbach, 1974; Renaer et al., 1979). Renaer et al. (1979) administered several psychometric tests to 15 patients with chronic pelvic pain without clear organic cause (group l), to 22 patients with chronic pelvic pain due to endometriosis (group 2), and to 23 controls without pain (group 3). Statistical analysis of the results showed that group 1 and 2 did not differ significantly on the M.M.P.I. (Minnesota Multiphasic Personality Inventory), and a

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global view of the two pain groups indicated neurotic behavior, but both groups 1 and 2 differed from group 3 (the controls) and from group 4 (the standardization group of the adapted M.M.P.I.). As it is improbable that chronic pain for which an organic cause has been found occurs predominantly in patients with neurotic personality structures or neurotic reactions, we must admit that chronic pain of organic origin can lead to neurotic reactions. These neuronic characteristics consist essentially of hypochondriasis, depression and hysteria. These conclusions are only a confirmation of the results of Woodforde and Merskey (1972) and of Stembach (1974). Characteristics

of psychogenic pain

Psychometric tests by themselves will therefore not be sufficient to distinguish patients with chronic pain problems due to organic lesions from those in whom no organic lesion has been found and whose pain is probably influenced or determined by psychogenic factors. Apart from the absence of organic lesions which could explain the chronic pain, the following criteria are useful for the diagnosis of psychogenic pain disorders: _ a pain description which is inconsistent with the anatomic distribution of the nerves involved; _ pain complaints which are grossly in excess of what would be expected from the physical findings; - pain which is associated with other sensory or motor functional changes, such as paresthesias, numbness or muscular weakness; - personality characteristics present during the premorbid period; _ a polysymptomatic pain syndrome; - variable pain complaints; - presence of a plausible psychological explanation such as one of the following (American Psychiatric Association 1980): a. A temporal relationship between an environmental stimulus that is apparently related to a psychological conflict and the initiation or exacerbation of the pain. b. Pain enabling the individual to avoid some activity noxious to him or her. c. Pain enabling the individual to get support from the environment that otherwise might not be forthcoming. As is well known, many of these patients have undergone extensive investigations or several pain-relieving operations. The relationship of peripheral noxious stimuli to pain In clinical practice there is frequently a discrepancy between the severity of tissue injury or, generally speaking, of the noxious event observed and the intensity of the suffering reported by the patient. Why this occurs is one of the fundamental problems of the study of the pain experience. Although they may entail more questions than answers a few remarks follow about the relationship between peripheral stimuli and chronic or recurrent pain as seen in gynecologic practice.

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(a) Peripheral mechanisms Gynecologists frequently wonder why some lesions found in the female internal genital organs cause chronic or recurrent pelvic pain while others do not. While endometriosis is frequently painful, some 30 to 40% of all patients with endometriosis do not complain of pain. Why do some have pain and others not? In some cases a sufficient explanation seems to be found in the characteristics of the lesions. According to Sturgis and Call (1954) ‘the lesions directly beneath or on the surface of the peritoneum may expand toward and bulge into the peritoneal cavity; on the other hand lesions buried deeply below the surface more likely call forth an enveloping response. This may be the most important aspect of the disease that determines whether or not there will be periodic pelvic pain’. At the macroscopic level this theory seems to be confirmed by the fact that endometriosis in a scar in the abdominal wall or in an episiotomy scar will provoke cyclic pain as long as the focus remains closed, and will become painless when it breaks through its capsula and opens on the surface of the skin. In most cases, the pain seems to result from an increase in intratissue pressure or from direct or indirect involvement of a nerve. Several reasons may be adduced to explain why many lesions are or become painless; but there remain a substantial number of cases which, inexplicably, are painless. It seems hardly possible to solve this problem either by histological examination of the nerves involved in the lesions, or by differentially measuring the intratissue pressure. A comparative psychometric study of the personality of endometriosis patients with and without pain could be undertaken; but any significant difference might be a consequence of the pain rather than its cause (Renaer et al., 1979). In the meantime, when confronted with a patient who complains of chronic or recurrent pelvic pain and who has endometriotic lesions, the conclusion should not necessarily be that the pain is due to endometriosis; rather, the question should be ‘How do I know whether this pain is due to endometriosis or not? (Renaer, 1981). The same reasoning holds for persons with painful sequelae of acute pelvic inflammatory disease (P.I.D.). Some people with chronic P.I.D. complain of pelvic pain, while others with an impressive hydrosalpinx or with tight pelvic adhesions do not. To date no satisfactory explanation has been given for these observations. Although we know that midcycle pain is somehow related to ovulation, much remains to be learned about the mechanism of the pain; but it is known that it is a syndrome and not just a symptom (Renaer, 1981). There is good circumstantial evidence suggesting that circulatory factors may give rise to chronic or recurrent pelvic pain. There is some hysterophlebographic evidence for the presence of passive pelvic congestion in some cases of chronic pelvic pain without obvious pathology (CPPWOP), but this passive congestion does not seem to be the sole factor at work in causing the pain. We therefore will have to await better methods for the differential evaluation of the pelvic circulation. But it is quite plausible that in some persons with symptoms of pelvic congestion this relatively minor visceral stimulus may become integrated in a complex of physiological or psychopathological circumstances that lead to complaints of chronic pelvic pain (Renaer et al., 1980).

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The mechanism of the pain remains unknown in many syndromes in which pain is an important symptom. In such cases it is tempting to look for a psychological or a psychopathological explanation. We believe that, in some instances, such an explanation is being accepted too readily. Indeed, a psychological explanation becomes plausible only when no organic or functional (i.e., pathophysiological) anomaly has been found and when, on the other hand, a psychological disturbance or psychopathological disorder has been discovered that can be considered the cause (and not the result) of the pain. If no such disturbance is found it seems preferable to classify the pain syndrome as ‘cause unknown’, rather than accept a psychopathological explanation too readily. There may, indeed, be an undiagnosed organic or pathophysiological cause (Leavitt and Garron, 1979). There are numerous papers which have explained primary dysmenorrhea along purely psychological lines. This subject is an excellent example of the caution that has to be exercised in these matters. There is indeed ample evidence that primary dysmenorrhea can be explained by pathophysiological mechanisms (Dawood, 1981; Lundstrom, 1981). Yet, although it cannot be denied that the pain experience of primary dysmenorrhea is influenced by psychological factors, ‘ there is no consistent evidence that dysmenorrhea is causally related to personality maladjustment, or exclusively related to psychological variables’ (Cox and Santirocco, 1981; Renaer, 1981). (b) Central mechanisms

Besides the peripheral events which influence or bring about pain experiences, there are several central factors or processes, emotional states such as anxiety or depression, cognitive factors such as attention or distraction, on the one hand; evaluation of the meaning of a noxious event, on the other; and finally, motivational aspects that will determine the kind of pain behavior the patient will adopt. It needs no stressing that the relationship between these various factors and the pain experience is complex. Pain and mood. Pain and psychiatric

illness

Anxiety tends to aggravate the pain experience. Therefore reassurance, when possible, and anxiolytics may help the patient when anxiety is a factor. Depression and pain are interrelated in at least two ways: chronic pain tends, for understandable reasons, to cause depression. Depression is associated with lower levels of pain tolerance, which will increase if the depression is treated (Bond, 1981). From a pathogenic as well as a therapeutic point of view it is important to recall that pain complaints are frequently encountered in depressive neurosis and in endogenous depression. Although much remains to be learned about the relationship between depression and pain, many depressive patients who complain of pain can be helped by antidepressive drugs (Pilowsky, 1981). Chronic pain frequently functions as a hysterical conversion symptom, i.e. ‘a symptom which results from an emotional conflict, is not directly related to bodily disease and is in accordance with the patient’s idea of loss of function in a part rather than with anatomy and physiology’ (Merskey, 1978).

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Factors influencing complaints and pain behavior

Pain experience and behavior are, inter alia, influenced by the meaning the pain has to the patient. Abnormal illness behavior with predominantly unconscious motivation may be seen in hypochondrical reactions which, according to Pilowsky (1981), may be either of the phobic or the somatic type. In the ‘phobic’ type the patient is preoccupied with the fear that the pains indicate the imminence of a serious illness. In the ‘somatic’ type the key feature is the preoccupation with the idea of disease itself; they are concerned with what they have at present rather than with what might happen in the future. Other important factors that may influence pain behavior are: personality factors, factors depending on the family, as well as cultural influences, and ‘operant’ behavior; i.e., behavior induced and maintained by environmental reinforcers. These diverse factors have been aptly reviewed in several recent studies, amongst which are those by Merskey (1978) and by Bond (1981). These behaviors are, inter alia, influenced by the extraversion-introversion dimension, by the neuroticism-stability dimension, by anxiety and, as mentioned earlier, by depressive, hypochondriacal or hysterical personality traits. The great influence of the learning processes the individual experiences in his familial and cultural environment need not be stressed here; but they should be acknowledged in the evaluation of the patient’s distress. Fordyce (1978) rightly insists on the importance of behavioral analysis of pain: it is necessary to search out the factors which may exert their influence on the pain behavior observed. This analysis is useful both from a diagnostic and a therapeutic point of view. Fordyce’s starting point is: ‘When considering chronic clinical pain, the question arises whether the pain behavior observed or reported is a consequence of an antecedent nociceptive stimulus or occurs, altogether or in part, because of environmental reinforcement’; in the latter instance we are dealing with ‘operant’ behavior. Clinical experience indicates that some mixture of both varieties of behavior is common. If early evaluation and treatment of a pain problem are effective the problem is solved and evolution towards chronicity is prevented. But unfortunately in many circumstances the pain behavior is allowed to become ‘operant’ either by direct or indirect reinforcement. Pain medications which are given too readily may act as direct reinforcers. There are, on the other hand, many examples of indirect reinforcement of pain behavior or, in other words, behavior leading to secondary gain, such as avoiding unpleasant work, or obtaining compensation, or complying with inappropriate advice against resuming one’s activities after an accident or an operation. Reflections on the management of chronic or recurrent pelvic pain

Pain complaints should always be taken seriously, even if they are not, or do not seem to be, symptomatic of a severe underlying disease. Patients should not be frightened by statements which have a ring of irreversibility, such as ‘varicosities’, which rarely cause pain, or ‘inflammation of the ovaries’ which is uncommon, and rarely painful. When conservative medical treatment, prescribed on a probability diagnosis,

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remains unsuccessful, a laparoscopy should be performed in order to make a correct diagnosis and to alleviate the anxiety of the patient more efficiently. As many lesions do not necessarily cause pain, a causal relationship between an observed anomaly and the pain complaint should not be taken for granted but should be accepted only after critical evaluation of the available evidence. If there are several pain localizations or pain complaints they may be due to two different disorders; patients with combined causes of pain are not exceptional. Long periods of rest with or without sickness benefit should not be prescribed unless they are really justified, and analgesics and sedatives should not be inconsiderately lavished on the patient as they may function as reinforcers of pain behavior. Family members should be advised against overprotective behavior, which may act as an indirect reinforcer. As a discrepancy between physical findings and pain behavior occurs frequently, enquiring into the problems, the personality and environment of the patient should go hand in hand with the search for an organic or functional cause. If a referral to a psychiatrist is deemed necessary, this should not needlessly traumatize the patient. The psychiatrist should be informed about the results of the examinations already performed, and a close collaboration should be maintained between gynecologist and psychiatrist. The countless ill-conceived, ineffective operations performed over the years on young women apparently have not yet taught some gynecologists _ that operation, especially in the domain of chronic or recurrent pain, frequently does not equal cure; - that an operation should only be resorted to when one is reasonably certain that a particular condition is the cause of the pain and that psychological factors are not likely to interfere with the results; _ and that the best deterrent against operating too readily is to reexamine at regular intervals and for at least two years every patient who has undergone surgery for chronic or recurrent pain. References Bond, M.R. (1979): Pain. Its Nature, Analysis and Treatment. Churchill Livingstone, Edinburgh, London, New York. Bond, M.R. (1981): Pain and Personality. In: Foundations of Psychosomatics, pp. 305-322. Editors: M.J. Christie and P. Mellat. J. Wiley and Sons, Chichester, New York. Bonica, J.J. (1979): The relation of injury to pain. Letter to the Editor. Pain, 7, 203-207. Cox, D.J. and Santirocco, L.L. (1981): Psychological and behavioral factors in Dysmenorrhea. In: Dysmenorrhea, pp. 75-94. Editor: Y. Dawood. Williams & Wilkins, Baltimore. London. Dawood, Y. (1981): Hormones, prostaglandins, and dysmenorrhea. In: Dysmenorrhea, pp. 21-52. Editor: Y. Dawood. Williams & Wilkins, Baltimore, London. Drossman, D.A., Sandler, R.S., McKee, DC. and Loritz, A.J. (1982): Bowel patterns among subjects not seeking health care: use of questionnaire to identify a population with bowel dysfunction. Gastroenterology, 83, 529-534. Fordyce, W.E. (1978): Learning processes in Pain. In: The Psychology of Pain, pp. 49-72. Editor: R.A. Stembach. Raven Press, New York. Hendler, N. (1981): Diagnosis and Non-surgical Management of Chronic Pain. Raven Press, New York. Janssen, R. (1981): Schmerzanalyse als Wegweiser zur Diagnose. G. Thieme, Stuttgart, New York.

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